- Author
- Pommersheim, J. M. | Clifton, J. R.
- Title
- Models of Transport Processes in Concrete.
- Coporate
- National Institute of Standards and Technology, Gaithersburg, MD Bucknell Univ., Lewisburg, PA
- Sponsor
- Nuclear Regulatory Commission, Washington, DC
- Report
- NISTIR 4405, September 1990, 101 p.
- Distribution
- Available from National Technical Information Service
- Keywords
- acid attack | chloride | concretes | convection | corrosion | degradation | diffusion | leaching | mathematical models | service life | sulfate attack | transport processes
- Abstract
- An approach being considered by the U. S. Nuclear Regulatory Commission for disposal of low-level radioactive waste is to place the waste forms in concrete vaults buried underground. The vaults would need a service life of 500 years. Approaches for predicting the service life of concrete of such vaults include the use of mathematical models. Mathematical models are presented in this report for the major degradation processes anticipated for the concrete vaults, which are corrosion of steel reinforcement, sulfate attack, acid attack and leaching. The models mathematically represent rate controlling processes including diffusion, convection, and reaction and sorption of chemical species. These models can form the basis for predicting the life of concrete under in-service conditions.